glslang ignores #pragma STDGL invariant(all)

[ShabbyX]

Take the following shader:

#version 450 core
#pragma STDGL invariant(all)

layout(location=0) out highp float v;

void main()
{
    gl_Position = vec4(v, v, 0, 1);
}

When compiled to SPIR-V, gl_Position should be decorated with Invariant. This is not done, and looking at the code of glslang, I didn't see it anywhere acting on this pragma.

Generated SPIR-V for the above shader is:

; SPIR-V
; Version: 1.0
; Generator: Khronos Glslang Reference Front End; 10
; Bound: 25
; Schema: 0
               OpCapability Shader
          %1 = OpExtInstImport "GLSL.std.450"
               OpMemoryModel Logical GLSL450
               OpEntryPoint Vertex %main "main" %_ %v
               OpSource GLSL 450
               OpName %main "main"
               OpName %gl_PerVertex "gl_PerVertex"
               OpMemberName %gl_PerVertex 0 "gl_Position"
               OpMemberName %gl_PerVertex 1 "gl_PointSize"
               OpMemberName %gl_PerVertex 2 "gl_ClipDistance"
               OpMemberName %gl_PerVertex 3 "gl_CullDistance"
               OpName %_ ""
               OpName %v "v"
               OpMemberDecorate %gl_PerVertex 0 BuiltIn Position
               OpMemberDecorate %gl_PerVertex 1 BuiltIn PointSize
               OpMemberDecorate %gl_PerVertex 2 BuiltIn ClipDistance
               OpMemberDecorate %gl_PerVertex 3 BuiltIn CullDistance
               OpDecorate %gl_PerVertex Block
               OpDecorate %v Location 0
       %void = OpTypeVoid
          %3 = OpTypeFunction %void
      %float = OpTypeFloat 32
    %v4float = OpTypeVector %float 4
       %uint = OpTypeInt 32 0
     %uint_1 = OpConstant %uint 1
%_arr_float_uint_1 = OpTypeArray %float %uint_1
%gl_PerVertex = OpTypeStruct %v4float %float %_arr_float_uint_1 %_arr_float_uint_1
%_ptr_Output_gl_PerVertex = OpTypePointer Output %gl_PerVertex
          %_ = OpVariable %_ptr_Output_gl_PerVertex Output
        %int = OpTypeInt 32 1
      %int_0 = OpConstant %int 0
%_ptr_Output_float = OpTypePointer Output %float
          %v = OpVariable %_ptr_Output_float Output
    %float_0 = OpConstant %float 0
    %float_1 = OpConstant %float 1
%_ptr_Output_v4float = OpTypePointer Output %v4float
       %main = OpFunction %void None %3
          %5 = OpLabel
         %18 = OpLoad %float %v
         %19 = OpLoad %float %v
         %22 = OpCompositeConstruct %v4float %18 %19 %float_0 %float_1
         %24 = OpAccessChain %_ptr_Output_v4float %_ %int_0
               OpStore %24 %22
               OpReturn
               OpFunctionEnd

[greg-lunarg]

Yes. This was never added for SPIR-V. I will add it.